ヒメセミエビの第 1 期フィロゾーマ幼生 ( 十脚目, セミエビ科 )

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1 ヒメセミエビの第 1 期フィロゾーマ幼生 ( 十脚目, セミエビ科 ) 誌名日本プランクトン学会報 ISSN 著者巻 / 号小西, 光一関口, 秀夫 37 巻 1 号掲載ページ p 発行年月 1990 年 8 月農林水産省農林水産技術会議事務局筑波産学連携支援センター Tsukuba Business-cademia Cooperation Support Center, griculture, Forestry and Fisheries Research Council Secretariat

2 Bulletin of Plankton Society of Japan Vol. 37 No. 1, pp , First-stage Phyllosoma of Scyllarus cultrifer (ORTMNN) (Decapoda, Scyllaridae) 1 ), 2 ) KOOICHI Ka NISHI 3 > ND HIDEO SEKIGUCHI 4 > National Research Institute of quaculture, Nansei-cho, Mie , ]apan 3 J and Faculty of Bioresources, Mie University, Kamihama-cho, Tsu, Mie 514, Japan 4 J bstract The larvae of the first phyllosoma stage of Scyllarus cultrifer (ORTMNN) is first described based on material hatched in the laboratory. The larvae belong to the second group which has four long plumose setae on the distal segment of second maxilla and are distinguished from the first group which is armed with three setae there. S. cultrifer is distinguishable from S. bicuspidatus, S. demani, S. sordidus, S. modestus and S. timidus in the following points: antennule armed with three aesthetascs, cephalon leaving the bases of third maxilliped uncoverd, third maxilliped and first pereiopod lacking coxal spines, exopod of the first and second pereiopods with five pairs of long plumose setae, and undeveloped fourth pereiopod. While, we failed to find any difference from S. depressus. S. bataei, S. martensii and S. rugosus cannot be compared with S. cultrifer because their description and illustration are brief. Out of the forty-three Scyllarus species of the world, phyllosoma larvae of sixteen species have been described based on laboratory or hauled materials (cf. SEKIGU CHI 1987). From Japan eight species of the Scyllarus, i.e. S. aurora, S. bicuspidatus, S. brevicornis, S. cultrifer, S. kitanoviriosus, S. longidactylus, S. martensii and S. rugosus, have been recorded, and morphological features of the first-stage phyllosoma larvae of these Japanese species have been known only for three species, S. bicuspidatus on the larvae hatched in the laboratory (SISHO 1964) and S. martensii and S. rugosus found in plankton samples (PRSD et al. 1975). It is necessary to examine laboratory-hatched material to insure true larva -adult parentage. The authors describe herein the newly-hatched phyllosoma of S. cultrifer which is the most common Scyllarus in the Pacific coast of Japan (SEKIGUCHI 1986). Materials and Methods On 30th June 1989, ovigerous females of Scyllarus cultrifer were taken with baited traps set on the sea floor (20 m depth) of the coastal water of Kumano-nada on 1) ccepted 11 July ) t ;t k ~ i t.:'v')m 1 JtlP ~ o '/-<:YJJ~ (+Jjtjl, k ~ i t.:'t4) 3) IF@J't-, ~U1UJf'.1'EJiJf 4) ~o~~ ~-*~~ ~$

3 78 the Pacific coast of central Japan. They were kept alive in an aquarium. Newly-hatched phyllosoma larvae appeared on 7th July. These larvae were immediately fixed in 5% buffered formalin and then preserved in 70% ethanol. ll figures were drawn with the aid of a drawing tube. scanning electron micrograph of mouth appendages was taken using usual techniques for SEM (QUINTN & KONISHI 1986). Body length was measured from the anterior margin of the cephalon (forebody) to the posterior end of the hindbody. Measurements were made with an ocular micrometer. The present phyllosoma larvae will be deposited at the National Science Museum in Tokyo after completion of the study. Results ll of the newly-hatched larvae were at the first-stage phyllosoma. No larvae of free-swimming naupliosoma or prephyllosoma stage were observed. Morphological features of the larvae are described below. The first-stage phyllosoma (Figs. 1-3) Body length ranged 1.06 to 1.13 mm, 1.11 mm in average; cephalon length ranged 0.55 to 0.61 mm, 0.59mm in average; cephalon slightly wider than long, nearly twice wider than hindbody, leaving the bases of third maxilliped exposed; abdomen slightly longer than 1/3 of hindbody length, narrow, not tapering much posteriorly, with a short spine and three small setae at each posterolateral angle; eye not stalked, shorter than antennule, antennule unsegmented and uniramous with three aesthetascs at apex plus a small spine at inner distal angle and with a small seta on inner margin slightly beyond middle of its length; antenna unsegmented and uniramous, about 1/5 length of antennule, with a terminal spine and a small seta at each side near distal end; mandible of scoop-shaped blade concealed under upper and lower labra, with two strong spines (incisor process) at the ventral angle followed by about six smaller, closely spaced teeth along the cutting edge of the blade separated by a narrow gap from the blunt projection surrounded by corneous teeth (molar process) at the dorsal end; first maxilla (Fig. 3) biramous and unsegmented without palp, coxal endite with a stout, elongated terminal seta and two shorter but similar subterminal setae, basal endite with two strong terminal and two small subterminal spines plus a small seta proximally near anterior margin; second maxilla consists of two segments, basal segment elongated, bearing a small seta on outer margin near distal end, distal segment small, narrow, with four long, plumose setae; first maxilliped wanting; second and third maxillipeds five-segmented without exopod, first segment of third maxilliped with a short spine and a small seta; first to third pereiopods well developed with a relatively short spine plus a small seta on first segment and an elongated, stout terminal claw on endopod, the first two pereiopods each with a stout subexopodal spine on endopod at base of exopod, exopod bearing five pairs of natatory setae, the third pereiopod with exopod as a small bud near middle of its second segment; fourth and fifth pereiopods wanting; pleopod and uropod wanting.

4 KONISHI & SEKIGUCHI: First-stage Phyllosoma of Scyllarus 79 Discussion Out of forty-three Scyllarus species in the world (SEKIGUCHI 1987) the first-stage phyllosoma has been described on eight species (S. americanus, S. bicuspidatus, S. demani, S. depressus, S. modestus, S. planorbis, S. sordidus and S. timidus) based on the larvae hatched in the laboratory (PRSD & T MPI 1960, SISHO 1964, ROBERTSON 1968, 1971, 1979 SNKOLLI & SHENOY 1973, RITZ 1977) and on three species (S. batei, S. martensii, S. modestus) based on those in plankton B D(FT ~ / ~~ E L. J B (O. lnvn)..., C - G (O. lnvn)., (1.0nvn) Fig. 1. Scyllarus cultrifer (ORTMNN). : dorsal view of whole body, B: antennule, C: antenna, D: mandible, E: first maxilla, F; second maxilla, G: abdomen.

5 80 samples (JOHNSON 1971, PRSD et al. 1975). These larvae are very similar in morphology each other. The first stage larvae of the present species also have common features with the above-mentioned species in the first and second antennae, second maxilla, second and third maxillipeds and so on. First-stage phyllosoma larvae of Scyllarus are separated into two groups by the number of long plumose setae on the apical segment of second maxilla (SEKIGUCHI 1987), three in S. americanus and S. planorbis (first group), and four in S. bicusjjidatus, S. demani, S. depressus, S. modestus, S. sordidus and S. timidus (second group). ROBERTSON (1979) described first-stage phyllosoma larvae of S. planorbis with second maxilla bearing three setae on the apical segment in the first stage, although he illustrated four setae in the same paper. s to S. sordidus, SNKOLLI & SHENOY (1973) illustrated and described second maxilla B ' / L J C-E L J B (0.2mm) E Fig. 2. Scyllarus cultrifer (ORTMNN). : second maxilliped, B: third maxilliped, C: first pereiopod, D: second pereiopod, E: third pereiopod.

KONISHI & SEKIGUCHI: First-stage Phyllosoma of Scyllarus 81 to bear two long plumose setae on the apical segment, while PRSD & T MPI (1960) and RITZ (1977) confirmed four setae, based on the

6 KONISHI & SEKIGUCHI: First-stage Phyllosoma of Scyllarus 81 to bear two long plumose setae on the apical segment, while PRSD & T MPI (1960) and RITZ (1977) confirmed four setae, based on the examination on hatched larvae in the laboratory. The present authors adopt that S. sordidus bears second maxilla with four setae on the apical segment, because the apical segment with two plumose setae is an abnormal feature in this genus. The present species belongs to the second group in having four long plumose setae on the apical segment of the second maxilla. From some species belonging to the second group this species is distinguishable as follows. S. bicuspidatus, which is the most closely allied species to S. cultrifer in size and external features, has four aesthetascs at apex of antennule, cephalon covering the bases of third maxilliped, and third maxiliped and first pereiopod lacking coxal spines. S. demani has six or seven pairs of natatory setae on the first and second pereiopods, non-setose exopod on the third pereiopod, and the bud-like fourth pereiopod as long as abdomen (RITZ 1977). S. sordidus has a unique shaped second antenna and seven pairs of natatory setae on the first and second pereiopods (PRSD & TMPI 1960). S. modestus and S. timidus have first and second pereiopods bearing six pairs of natatory setae (JOHNSON 1971, RITZ 1977). The present species is difficult to be separated from S. depressus (ROBERT SON 1971). The first-stage phyllosoma of S. batei, S. martensii and S. rugosus were reported by PRSD et al. (1975). However, we cannot compare the present species with the three species mentioned above because their description is very brief and the illustration is so small that the number of plumose setae on the apical segment of second maxilla cannot be confirmed. Fig. 3. Scyllarus cultrifer (ORTMNN). Scanning electron micrograph of first maxilla (M). ( x 410)

7 82 cknowledgment This work was supported in part by a Grant-in-id (Bio Cosmos Program) from the Ministry of griculture, Forestry and Fisheries. Literature Cited JOHNSON, M. W., The phyllosoma larvae of slipper lobsters from the Hawaiian Islands and adjacent areas. Crustaceana, 20: PRSD, R. R. & P. R. S. T MPI, On the newly hatched phyllosoma of Scyllarus sordidus (STIMPSON). ]. mar. biol. ss. India, 2: PRSD, R. R., P. R. S. T MPI & M. J. GEORGE, Phyllosoma larvae from the Indian Ocean collected by the Dana Expedition ]. mar. biol. ss. India, 17: QUINT N, R. & K. KONISHI, On the prezoeal stage: observation on three Pagurus species (Decapoda, nomura). ]. nat. Hist., 20: RITZ, D.., The larval stages of Scyllarus demani HOLTHUIS, with notes on the larvae of S. sordidus (STIMPSON) and S. timidus HOLTHUIS (Decapoda, Palinuridea). Crustaceana, 32: ROBERTSON, P. B., The complete larval development of the sand lobster, Scyllarus americanus (SMITH), (Decapoda, Scyllaridae) in the laboratory, with notes on larvae from the plankton. Bull. mar. Sci.,18: ROBERTSON, P. B., Biological results of the University of Miami: Deep-sea expeditions 84. The larvae and postlarva of the scyllarid lobster Scyllarus depressus (SMITH). Bull. mar. Sci., 21: ROBERTSON, P. B., Larval development of the scyllarid lobster Scyllarus Planorbis Holthuis reared in the laboratory. Bull. mar. Sci., 29: SISHO, T., Notes on the first stage phyllosoma of scyllarid lobster, Scyllarus bicuspidatus. Mem. Fae. Fish. Kagoshima Univ., 13: 1-4. SNKOLLI, K. N. & S. SHENOY, On the laboratory hatched six phyllosoma stages of Scyllarus sordidus (STIMPSON).]. mar. biol. ss. India, 15: SEKIGUCHI, H., Spatial distribution and abundance of phyllosoma larvae in the Kumano-nada and Enshu-nada seas north of the Kuroshio Current. Bull. Japan. Soc. Fish. Oceanogr., 50: SEKIGUCHI, H., Life histories of the scyllarid and palinurid lobsters-12. Kaiyo to Seibutsu (quabiology), 9: (In Japanese)

水槽中で培養したマコンブ胞子体の子嚢斑形成と生長におよぼす水温及び光周期の影響

水槽中で培養したマコンブ胞子体の子嚢斑形成と生長におよぼす水温及び光周期の影響水槽中で培養したマコンブ胞子体の子嚢斑形成と生長におよぼす水温及び光周期の影響誌名水産増殖 = The aquiculture ISSN 77 著者巻 / 号桐原, 慎二藤川, 義一能登谷, 正浩巻号掲載ページ p. 8-9 発行年月年月農林水産省農林水産技術会議事務局筑波産学連携支援センター Tsukuba Business-Academia Cooperation Support